Ai; Hai

Boyd’s Bible Dictionary:

(heap of ruins). (1) An ancient city of Canaan (Gen. 12:8), where it is spelled HA’I. Captured and destroyed by Joshua ({vi 5980-5982;6041;6066;6140}Josh. 7:3-5; 9:3; 10:1; 12:9). Written Aiath (Isa. 10:28); and Aija (Neh. 11:31; Ezra 2:28). (2) A city of Heshbon (Jer. 49:3).

Concise Bible Dictionary:

1. Royal city of Canaan. It was known to Abraham, who pitched his tent between Hai and Bethel (Gen. 12:8). It was conquered by Joshua — after a repulse because of the sin of Achan — by a stratagem; it was burnt and made a “heap” ({vi 5979-5982}Josh. 7:2-5; {vi 6004-6032}Josh. 8:1-29; {vi 6066-6067}Josh. 10:1- 2). It was near Bethel, in Benjamin’s lot, and apparently rebuilt, for it is mentioned in Ezra 2:28 and Nehemiah 7:32. It is probable that the AIATH of Isaiah 10:28 and the AIJA of Nehemiah 11:31 are the same as Ai, by the places named in association with them. In the district there are ruins scattered along the narrow summit of a ridge, and a depression among the rocky heights well suited for an ambuscade such as Joshua employed. The ruins are called Haiyan, 31° 55' N, 35° 16' E. Travelers say that when on the spot, the Biblical narrative of the capture of Ai can be vividly realized.
2. City of the Ammonites, unknown (Jer. 49:3).

Jackson’s Dictionary of Scripture Proper Names:

same as Ai, with article; "the heap"